1. Field
Exemplary embodiments of the present disclosure relate to light source and display device technology.
2. Discussion
Examples of a flat panel display include a self-light emitting type display device emitting light by itself, such as a light emitting diode display (LED), an electric field emission display (FED), a vacuum fluorescent display (VFD), and a plasma display panel (PDP), and a light receiving type display device that does not emit light by itself but, instead, requires a light source, such as a liquid crystal display (LCD) and an electrophoretic display.
A display device including a separate light source among the light receiving type display devices may be a transmission type, and the transmission type display device includes a display panel displaying an image and a backlight unit supplying light to the display panel. The backlight unit includes a light source module emitting light, various optical sheets, and the like. The light source module may include at least one light source package, and each light source package may include a light source (also commonly referred to as a light emitting element). Examples of light sources include a cold cathode fluorescent lamp (CCFL), a flat fluorescent lamp (FFL), a light emitting diode (LED), and the like. Recently, a light emitting diode (LED) having small power consumption and small caloric value has been frequently used as a light source.
Accordingly, display technologies are typically configured so that light can be uniformly radiated on a rear surface of a display panel of the backlight unit, such that the backlight unit may be classified into a direct lighting type backlight unit, an edge type backlight unit, and the like, according to the position of the light source module. The direct lighting type backlight unit having a light source module will typically radiates light directly on the display panel, whereas the edge type backlight unit having a light source module will conventionally be provided on one side or both sides of a light guide so that light may be diffused through the light guide and, thereby, be indirectly radiated on the display panel.
The light source module of the backlight unit generally includes light source packages emitting lights of different colors in order to emit light of a white color, and light of the generated white color may be obtained by synthesizing lights of different colors emitted from each light source package. In this case, color stains may be formed on an image displayed on the display panel according to arrangement of the light source packages and the color of light emitted from the light source packages. For example, in the case where the color of the light source package corresponding to one edge of the display panel and the color of the light source package corresponding to another edge of the display panel are different from each other, the colors of both edges of the display panel may be differently viewed and, thereby, perceived as color stains.
Meanwhile, backlight units are typically divided into a plurality of light emitting blocks and the light emitting blocks are separately driven according to a driving method (or scheme) of the display device. For example, the backlight unit may be divided into a plurality of light emitting blocks and luminance of light emitted from each light emitting block may be controlled in order to prevent a contrast ratio of the display device from being reduced, as well as to minimize power consumption. This is generally referred to as a local dimming driving method. Further, in the case of three dimensional (3D) image display devices, when a display panel is divided into a plurality of display blocks and the display blocks are each sequentially driven, cross-talk phenomena, whereby a left eye image and a right eye image are perceived to overlap, may be prevented by dividing the backlight unit into a plurality of light emitting blocks corresponding to each display block and sequentially driving the display blocks to emit light.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form any part of the prior art nor what the prior art may suggest to a person of ordinary skill in the art.